A demand response means changes of an electric power consumption pattern so that consumers will temporarily refrain from the use of electric power, by means of changes of electric rates or payments of remuneration at the time of a rise in wholesale market prices or degradation of system reliability. In the electric power trading market such as the U.S., not only electric power generated by power plants, but also electric power called “negawatts” created by the demand response is traded.
Moreover, in recent years, traders called “aggregators” who organize negawatts of small-scaled consumers and deal with electric power companies and system operators have appeared. There are growing concerns about destabilization of electric power demand balance and expansion of volatility of electric power prices due to expansion of the electric power generation by regenerated energy; and in that sense as well, effective utilization of the negawatts as organized by the aggregators is expected.
Normally, an aggregator enters into a contract called a “demand response program” with consumers or another aggregator who organizes consumers in order to create the negawatts. When the consumers complete registrations to join the DR program, it becomes possible for the aggregator to use these consumers' equipment as resources to create the negawatts.